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The purpose of this paper is to present a method for ultrasonically molding polymer powder in a micro plastic part mold. In the method, a printed circuit board (PCB) in which micro‐hole arrays are drilled is used as a micro cavity insert. With the utilization of ultrasonic vibration, the polymer powder, which is prefilled and compacted in a micro cavity, mutually generates great sliding friction heat so as to be rapidly plasticized and molded.

Micro carbide drill bits of which the diameters are 100.0 μm, 150.0 μm and 200.0 μm, respectively, are used for drilling the PCB to form a micro‐hole array insert. Next, two kinds of various ultra‐high molecule weight polyethylene (UHMW‐PE) powder with various grain diameters are directly filled into a charging barrel and a mold cavity with the micro‐hole array insert. Proper process parameters are set on ultrasonic plasticizing and molding equipment so that a molding test can be performed. The melt of UHMW‐PE can be rapidly filled into the cavity. Finally, micro‐column array plastic parts are successfully prepared.

The micro‐hole array PCB is a mold insert which is quite applicable for the ultrasonic molding of the powder in the mold. When a molding material is the coarse UHMW‐PE powder with the grain diameter of about 350 μm, the diameter replication rates of the micro‐column array plastic parts become good in order with the increased micro‐hole diameter of the PCB. When the fine UHMW‐PE powder with the grain diameter of about 80 μm is adopted, the diameter replication rates of the micro‐column array plastic parts become good in order with the decreased micro‐hole diameter of the PCB.

In this paper, the micro‐column array plastic parts with good replicability are successfully prepared by a technique for ultrasonically plasticizing and molding in the cavity. The technique can be applied to the fields of medical treatment, communication, optics, chemistry and so on, such as biological micro needle arrays, micro biological chips, optical memories, and micro chemical reaction chips.

Guanidine stearate will function as a lubricant for melamine/formaldehyde resins (and guanamine/formaldehyde resins), and glyceryl monostearate can improve the mechanical properties of the former. Laurie acid can be applied to the production of high grade baking enemel resins in combination with melamine. Stearic acid can be used in the manufacture of melamine resins, e.g. by reaction with formaldehyde and butanol, to give resins for lacquers, and to yield moulding resins. Sodium myristate is usable as a chain transfer agent in the emulsion polymerisation of methyl methacrylate. Copolymerisation of methacrolein dibutyrate and methyl methacrylate has given resins that can be moulded or used in varnishes, and reaction products of stearic acid with methacrylic acid and neodymium oxide has given transparent optical resins. Cellulose laurate can produce extensibilities of nitrocellulose of the order of 100%, and cetyl acetate can act similarly in film, having little tendency to yellowing, but it has also little stability to exterior exposure. When ethylene glycol monmethyl ether acetyl ricinoleate is incorporated into nitrocellulose as a plasticizer, it gives films that are clear, tough and flexible. Stearic acid can act as a stabilizer for nitrocellulose. Lauryl phosphate has been applied as a catalyst in the modification of olefinic petroleum results, by reaction with acrylic resins, and distearyl pentaerythritol diphosphite can function as a heat stabilizer in petroleum resins.

This paper aims to emphasize compared experimental analysis of influence of hybrid and classic moulds on the properties of moulded parts and the processing parameters. Such analysis enables optimization of processing parameters in case of the hybrid mould.

Representative moulded part and appropriate hybrid and classic moulds have been designed and manufactured. The experimental work contains a screening design and the main central composite design for analysing the performance of both moulds and moulded parts properties. In case of hybrid mould a numerical optimization of processing parameters was used.

It was found that hybrid moulds can be successfully applied for production of thin‐wall moulded parts with some limitations. The compressibility of prototype mould inserts was higher compared to classic inserts. The differences in thermal properties of mould inserts materials result in different moulded part properties and mould cavity wall temperature fields. These differences can be reduced by optimizing the processing parameters.

RT technologies can be usefully applied for fast production of moulds for injection moulding. The potential user of hybrid moulds should be aware of the influence of prototype inserts on the moulded part properties. Guidelines for optimization can be used for fast achieving of parameters from optimal processing window.

This paper shows a detailed analysis of influence of hybrid and classic moulds on the thermoplastic moulded part properties. Some of these influences are explained in detail, which was not found in the related papers. In this paper, a further step was made by optimizing the processing parameters in case of hybrid mould.

This paper aims to improve the efficiency and the quality of metal dental prostheses, reporting on the first patient‐fitted titanium (Ti) complete denture base plate fabricated by integrating the technologies of computer‐aided design and computer‐aided manufacture (CAD/CAM) and laser rapid forming (LRF).

To make a complete Ti denture base plate, the traditional lost‐wax‐casting technique is commonly used in dentistry. In order to simplify this labor‐intensive process, a new method combined with LRF was invented. Initially, a maxillary edentulous plaster cast was converted to point cloud data by laser scanning system. Subsequently, point cloud data were reconstructed into a 3D solid digital cast, which is stored in standard triangulation language format. Thereafter the 3D denture base was sliced electronically into a sequence of layers defining the regions of the component and, based on it, the complete Ti denture base plate was built layer‐by‐layer using a laser additive manufacturing technology.

After CAD/CAM/LRF process, the Ti denture base plate was designed and successfully fabricated layer‐by‐layer. After the traditional dental finishing techniques, the complete Ti denture base plate was made and assessed by clinician and patient. The clinical evaluation on quality of fit was judged to be acceptable.

The CAD/CAM/LRF system is a potential candidate to replace the traditional lost‐wax‐casting technique and provides a new platform for the design and manufacturing of custom‐made Ti denture plates and other restorations especially for implant substructure and framework of partial removal of denture.

The purpose of this paper is to review the robots at the 2007 ATExpo Show and related Electronics Assembly Show, Quality, PlasTec and National Manufacturing Week Shows, as well as at the FABTECH Show and the Rockwell Automation Show held in Chicago.

The paper incorporates in‐depth interviews with robot exhibitors, as well as suppliers of accessories such as grippers and simulation software.

Each show brings forth innovations in robotics. After many decades of robot developments, the well‐spring of innovation never seems to dry up.

If an application cannot appear to be addressed by the robot of the day, wait until tomorrow and suppliers will step forward with answers. After more than four decades of robot development, they continue to get smarter, much faster and better adapted to application requirements. There is no longer a one robot “fits all” answer.

This paper provides information on prevailing trends in the robot industry which solve an increasing number of application needs.

The purpose of this paper is to determine the most‐practical means of transforming computer‐aided‐design models of custom clubfoot pedorthoses into functional pedorthoses for testing on patients in a clinical trial.

The materials used in conventional orthosis fabrication are not yet available for solid free‐form fabrication; therefore, to fabricate the pedorthoses, several approaches were considered, including direct manufacturing, additive‐based moulding, laser cutting of foam and combinations of several of these approaches.

The chosen approach of additively manufacturing the custom hard shell, and moulding the polyurethane‐foam insert, resulted in accurate, durable and effective pedorthoses that fit well, and could be adjusted as needed. The pedorthoses that were produced are currently being tested on the respective patients for their improvement in mobility and degree of clubfoot correction, and will continue through early 2010.

Additive manufacturing provides an ideal approach for generating the custom, end‐use hard‐ and soft‐layer patterns: each pedorthosis is truly unique; and the soft layer has regions of variable thickness. The advantage of this approach is the reduction in labour and the increase in degrees of design freedom available, compared to conventional methods of fabricating orthotic devices. Replacement inserts can be moulded in a matter of hours using this silicone‐moulding approach.

Several new approaches for fabricating custom orthotic devices were explored, and the related results are discussed. The goal of this paper is to convey the potential of the fabrication procedure used and lessons learned on this project to the rapid prototyping and orthotic communities.

The purpose of this paper is to present a numerical and mathematical model of a moulding process of a dry electrical transformer. Moreover, the calculated results are reported and compared with experimental measurements.

An experimental rig, for carrying out and monitoring a moulding process, has been designed and built. Two experiments were preformed. First was an isothermal experiment in which an analog liquid was used. The second experiment was a non‐isothermal one in which an epoxy resin was used. For the rig geometry, the numerical mesh, with the use of the commercial code Gambit, was built. All necessary physical properties, including viscosity, surface tension and contact angle of fluids used in the experiments were measured.

The Euler approach for modelling multiphase flow with a free surface is addressed in the presented work. Comparison of the computational results with measurements on the designed experimental rig revealed good agreement. Comparison was carried out through measurements of free surface characteristic features captured with a digital camera and through temperature measurements for the nonisothermal case. Richardson extrapolation method was successfully applied to estimate the numerical discretisation error, proving that a grid independent solution was obtained.

This paper is useful for researchers and industrialists involved in the modelling of moulding processes, giving guidance on the available mathematical models appropriate for this kind of problem. Moreover, it provides valuable information as to how to perform validation and verification procedures for such real‐life processes.

This study was aimed to develop and evaluate nutritional efficacy and bio-efficacy of food products from plantain, soycake, rice-bran and oat-bran flour.

The flour samples were blended as follows: plantain 70% and soycake 30% (PS); plantain 65%, soycake 30% and rice bran 5% (PSR); plantain 65%, soycake 30% and oat bran 5% (PSO); and plantain 60%, soycake 30%, rice bran 5% and oat bran 5% (PSRO). Antioxidant and nutritional properties of the blended foods and controls (100% plantain and Cerolina) were determined.

Protein (16.2–19.4 g/100g) and biological values (98.5–99.3%) of the food samples were significantly (p = 0.03) higher than 100% plantain (5 g/100g, 31.6%) and Cerolina (17.9 g/100g, 98.3%). Pack cell volume (36.2–42%), serum protein (7.3–9.3 mg/dL), urea/creatinine (1.1–2.8) and aspartate-aminotransferase/alanine-aminotransferase ratio (0.9–1) of the foods were significantly (p = 0.03, 0.01, 0.02 and <0.01, respectively) higher than 100% plantain (28%, 1.6 mg/dL, 4.6 and 0.8) and Cerolina (46%, 4.9 mg/dL, 3 and 0.73). In vivo antioxidant activity of the food samples decreased from PSRO to PSO, PSR and PS, respectively and were higher than control samples. Nutritional performance of formulated foods in rats was similar to that of Cerolina, but higher than in 100% plantain. Cerolina and 100% plantain were rated higher in overall acceptability than formulated foods; however, PSO was most preferred followed by PSRO for the formulated foods.

The study established that PSRO was rated best in terms of nutrition, growth performance and antioxidant activities. Hence, this food may be suitable as functional food to prevent malnutrition and oxidative stress.

In this work, the changes to stereolithography (SL) resin mechanical properties during the injection moulding process were evaluated. A multi‐impression SL mould was built and used to inject a series of small flat mouldings. The fixed half SL tool insert included recesses to accommodate tensile test specimens. Tensile test specimens made from SL resin were positioned in these recesses and plastic parts were injected. After injecting a predetermined number of mouldings, tensile tests were performed using the tensile test specimens. The results from the tensile tests show that the thermal cycling encountered during the injection moulding process did not significantly affect the mechanical properties of the resin. Observations indicate that decrease in the temperatures encountered in the tool may lead to longer tool life.

This paper presents a study on implementing design of experiments for optimizing the extrusion blow molding process. The effect of screw speed, melting temperature, cooling time, pressure, mold temperature, and ambient temperatures on the outcome of the process is investigated. The significant factors affecting the volume and mass of the blow molded bottles are identified. The results show that melting temperature, pressure, and ambient temperature have a significant impact on the variation of produced bottle quality. An optimization technique is implemented to identify the best operating conditions to meet the required product output.